OT: Electronics store with classic parts [telecom]

What, doesn't everyone remember the AA5? It was the most common design of vacuum tube AM radio, especially common for clock radios. It had five vacuum tubes. The main feature was its cheapness, its ability to avoid having a power transformer. The tubes had filament voltages that added up to 117 volts, and were wired in series with each other.

While I remembered this in vague terms, the wackpedia has an article about it, listing several generations of AA5 tube sets. I only remembered the miniature-tube version, which was my bedside clock radio for some years.

-- Fred Goldstein k1io fgoldstein "at" ionary.com ionary Consulting

Can't clearly remember 'em any more (Alzheimer's ?), but ...

.. they were the tube complement in all the classic, el cheapo, AC/DC superheterodyne table top sets of the early-to-mid '50s. Wait: maybe my old RCA Receiving Tube Manual has a schematic? ... (comes back) ... YES:

'Zat what you were after, Bill? Or were you looking for the post-octal follow-up to these (their miniature 9-pin counterparts)? Cheers, -- tlvp

Could you elaborate on what those tubes are and what they're used for? I thought by now even high power applications were converted to solid state.

Thanks.

(Today I passed a former AT&T Long Lines microwave antenna site. I read that it's no longer used for that, but merely a platform for cell phone antennas.)

Well, let's see: Magnetrons are vacuum tubes, right?

Bill Horne Moderator

Add an extra 12BA6 and an IF can, and a 6C5 for a BFO. Replace the 50C5 with a 35C5 to make up for the extra filament load. Take some winds off the loopstick to move it up to the shortwave bands. Voila, ham receiver for $10 or so.

Those are the 7-and 9-pin minis. I don't remember the early octal ones, but they weren't quite as standardized.

--scott

(Ulp!) You're right, scott. So much of that RC-18 *is* octal stuff I never bothered checking whether those 5 were or weren't, just assumed they were.

Sorry to have misled so badly! And thanks for steering us all right again.

Cheers, -- tlvp